如何在Ruby on Rails中不使用按钮的表单上进行验证？

def new
  @user = User.new
end

<%= form_with(model: @user, local: true) do |form| %>
  <%= form.text_field :name %>
  <%= form.email_field :email %>
  <%= form.password_field :password %>
  <%= form.password_field :password_confirmation %>
  <%= form.submit %>
<% end %>

class User < ApplicationRecord
  validates :name, presence: true
  validates :email, presence: true, format: { with: URI::MailTo::EMAIL_REGEXP }
  validates :password, presence: true, length: { minimum: 6 }
  validates :password_confirmation, presence: true
end